Add onPrimary variant to KeybindingHint

[iansan5653]

Adds an onPrimary variant to KeybindingHint to close #5351 and improve the appearance of primary button hints:

This is a temporary fix until we have a more full-featured design spec for this component, at which point we can implement this in a better manner. I don't really love the onEmphasis/onPrimary variant names, but it's consistent with what's there and doesn't break anything.

Changelog

New

Adds an onPrimary variant to KeybindingHint for use on primary buttons

Changed

Removed

Rollout strategy

• Patch release
• Minor release
• Major release; if selected, include a written rollout or migration plan
• None; if selected, include a brief description as to why

Testing & Reviewing

Merge checklist

• Added/updated tests
• Added/updated documentation
• Added/updated previews (Storybook)
• Changes are SSR compatible
• Tested in Chrome
• Tested in Firefox
• Tested in Safari
• Tested in Edge
• (GitHub staff only) Integration tests pass at github/github (Learn more about how to run integration tests)

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🦋 Changeset detected

Latest commit: 2ab4c4d

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@primer/react	Minor

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[github-actions]

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[github-actions]

👋 Hi, this pull request contains changes to the source code that github/github depends on. If you are GitHub staff, we recommend testing these changes with github/github using the integration workflow. Thanks!

[github-actions]

size-limit report 📦

Path	Size
packages/react/dist/browser.esm.js	102.79 KB (+0.07% 🔺)
packages/react/dist/browser.umd.js	103.12 KB (-0.02% 🔽)

[langermank]

Nice!

[iansan5653]

I didn't add an onDanger variant since danger buttons have a light resting background that works OK with the current design. Just added a story to demonstrate that